I have cycled my 29g FOWLR and levels were all good with 2 small yellow tail damsels, 0 ammonia, 0 nitrites, 30 nitrates. I added a clown and a cardinal and checked my levels, my ammonia is still at 0 but my nitrites moved to .25! Grrrrrr!! What should i do? water change or just let it ride out? thanks

Do one asap. You dont have enough bacteria to support them fish right at this point. It's not your fault if you followed the cycle process. But yeah, Just water change and bring it down. Wait a couple of months before adding another fish if you are. 1 to 2(If they're small, e.g gobies or more cardinals) more fish will do it for 29g.

Too many fish at one time. I would consider getting rid of the damsels as damsels are known for being aggressive towards other fish, and that would free up your bioload and allow you to add more fish a few months down the road. Allow you tank to stabilize for a few months before you add anything else. Moving too fast will get you into trouble, so slow down a bit. Hope this helps.

Ahhh, I miss read you had damsels. Yeah, Your stocked out for sure. As Thom said, Get rid of the damsels.

I have 2 Electric Blue Damsels (Not being a hipocrit), They're good to watch but when i add new fish its on. I added a blue tang recentaly which mind you is 5x or more its size and it was still trying to nip it. The blue tang wasnt fussed and they're fine now. I wish i never added them though.
When ever i put my hand/arm in the tank his always biting me.

I did a 20% WC that evening, bring the nitrites down to between .25 and 0. Check it the next day (Saturday) and it was at zero. Checked it again today and it is still at zero.

I was initially concerned about the yellow tails and will still probably take them back just to free up some bio-load for something i would rather have. But that said, they have actually been very good citizens and nieghbors to the new additions. And the really strange thing is that only "aggressive" behavior i have seen, if you want to call it that, was from the cardinal, that's weird. Thanks for all the help.